Today, nanomaterials are receiving increasing attention, as they exhibit exciting and useful attributes that can be employed across applications and disciplines range from electronics to drug delivery. This dissertation focuses on two disparate projects, both related to plasma-synthesized nanocrystals. The two projects highlight the unique properties of nanocrystals, and their sustainable synthesis using gas phase approaches. These methods apply non-thermal plasma reactors for nanocrystal synthesis. First, we introduce a plasma-based gas phase method for Gold nanoparticle (AuNPs) synthesis. Second, we use plasma-synthesized Silicon nanocrystals (SiNCs) in bilayer and composite structures with a commonly used elastomer, to investigate the mechanical behavior of the structures in a first-of-its kind investigation. There are many applications for AuNPs due to their interesting optoelectronic properties, such as tunable optical absorption and plasmonic resonance behavior. While synthesis and stabilization of colloidal AuNPs is well-established, new synthesis routes can lead to enhanced versatility of applications for AuNPs, particularly if the methods allow avoidance of solution processes or surfactants. In Chapter 2, we introduce a plasma-based synthesis of AuNPs, using a consumable gold wire and a radiofrequency power source. The AuNPs are monodisperse, with an average diameter of 4 nm. While production yield is low, the narrow size distribution of the AuNPs and the avoidance of solution processing in this method are promising for future syntheses of metal NPs based on plasmas.Next, a comprehensive analysis of the mechanical behavior of SiNC/PDMS systems, using plasma-produced SiNCs has been performed. Chapter 3 details our experimental methods combined with modeling to estimate the mechanical behavior of thin layers of SiNCs on PDMS, as deposited directly onto the PDMS from non-thermal plasma reactor. For the first time we estimated the mechanical behavior of thin films of SiNCs by using the onset of bifurcations as an indicator of their modulus. Next, reaching towards luminescent nanocomposites for applications in luminescent devices, we investigated the optical and mechanical behavior of blended SiNC/PDMS nanocomposites. The results from these investigations, reported in Chapter 3 and Chapter 4, have shed light for the first time on the interactions between SiNCs and PDMS both in bilayer and composite structures, pointing to future optoelectronic and opto-mechanical device applications with predictable properties.Finally, in Chapter 5, we share ongoing projects which will be finalized soon, as well as detailing future work surrounding these ideas. We share our parametric study to uncover the various effects of surface functionality, SiNC layer thickness, and PDMS modulus on the resulting SiNC thin film. Concurrently, we probed the formation of wrinkles and cracks on SiNC film surfaces, which were deposited on pre-stretched PDMS using a finite bending configuration, to examine how instabilities on the thin films can be predicted.
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